Yes it won't happen overnight. Many hours and days on the water. There are so many great Youtube videos out now.
Yes a bigger boat is almost always longer and wider, and hence more volume.
Maybe adding 5-10 litres of water into your boat can help with the plowing ender in the initial stages, just to get the feeling of how it should feel. When you're at the bottom end of the weight spectrum you always need more power and more technique. If you can, get someone to video you and post it. That way you can learn the fastest